This article analyzes the constitutionalization process of political parties in Poland and the evolution of party system in the years 1918–2018. It is an analysis of political parties in Poland that draws on political science methods and legal studies methodology. We use a concept by Heinrich Triepel, who constructed a four-phases model of relations between parties and the state. The phases are: the abatement of parties (Stadium der Bekämpfung), the ignoring of parties (Stadium der Ignorierung), acknowledgement and legalization (Periode der Anerkenung und Legalisierung) and constitutional incorporation (Ära der verfassungβmasigen Inkorporation). Upon regaining its independence in 1918, Poland entered the third phase. It was not until 1989 that Poland entered the phase of constitutionalization of parties. The methods we employ are historical analysis, document research and comparative analysis. In the article we discuss the evolution of Polish party system and divide it into periods: first spanning from 1918 till 1939, second starting in 1944 and ending in 1989, the last one beginning in 1990. We conclude that the party system in Poland after 1989 underwent a long process of changes. It moved from a system of extreme party fragmentation to a system of imperfect bipartisan competition. What is more, the process of stabilization of electoral law and the institutionalization of political parties contributed greatly to the consolidation of the Polish party system.

The aim of the article is to indicate the prevalent features of the Polish process of constitutional and systemic changes in Poland in 1989-1997. It was assumed that the Polish process of constitutionalization was characterized by a number of specific features which were interrelated and dependent on each another. The aim of the paper is to recognize the phased character of the changes as the first feature of the political transformation process in Poland, whereas compromise should be regarded as its basic attribute. Other specific features (presented in the subsequent parts of the article) include: evolutionary, temporary, and pragmatic nature of the process.